The following abbreviations are used for describing the invention:
GNC: Guidance, Navigation and Control
NGC: Navigation, Guidance and Control
IMU: Inertial Measurement Unit
GPS: Global Positioning System
CAS: Control Actuator System
LOS: Line of Sight
VTOL: vertical take off and landing
OLED: organic light emitting diode
DoF: Degree of freedom
It is known from the prior art that, for the development of missiles, it is frequently necessary to carry out flight tests. In this case such flight tests are a cost driver in the development of missiles, which needs to be reduced in particular in order to increase competitiveness. Because of a large number of staff, as well as the required use of equipment, infrastructure and safety aspects, flight tests are associated with high financial expenditure. Especially in the initial phase of a project for missile development, the flight tests sometimes have contrary purposes. This is due to the different requirements of the various disciplines participating in development of a missile. Thus, for example, it is important for the GNC developer to be able to fly as far as possible in order to be able to test the GNC functionality for as long as possible. On the other hand, it is a concern of the image processing development to be able to fly as realistically as possible to a real target in order to obtain image data for the corresponding algorithm. The duration of flight tests is generally much too short to be able to carry out all tests. Experience shows that malfunctions also often occur, so that flight tests cannot provide evidence and therefore have to be repeated. For these reasons there are attempts to avoid flight tests and instead to replace them by laboratory tests.
In conventional “hardware in the loop” testing systems, which take place in a laboratory, rotational degrees of freedom of the missile are simulated with a turntable or a robot. In this case, the “degree of freedom” designates the number of possibilities for movement of the missile which are independent of one another. Thus, the missile has six degrees of freedom, since it is movable in three spatial directions which are independent of one another and is rotatable about three axes which are independent of one another.
However, due to the fixed construction in a laboratory it is a disadvantage that the translational degrees of freedom and all functions associated therewith cannot be tested under realistic conditions. The relative geometry between the missile and a target to which the missile is to fly must be produced artificially, which happens in the prior art for example by values of the missile calculated by simulation. These values are then artificially fed into the missile avionics instead of the actual values. As such, it is important to know the behavior of the relevant systems, such as IMU, seeker head, GPS, etc., during the flight.
In practice, it has been shown that this behavior in the real flight is often substantially different from the behavior which can be observed in the laboratory. Likewise, for optical seeker heads, the geometric conditions which are important for the entire chain of reconstruction of the line of sight and guidance of the line of sight, such as aspect angle, aspect ratio, proximity, image explosion or environmental disturbances, can only be insufficiently and artificially adjusted. If realistic data are required, for example from a seeker head, there is a possibility of carrying out carried flights on man-carrying aircraft, such as an airplane or helicopter. These carried flights are very expensive and often more expensive than real flight tests, due to the high use of resources and safety aspects. For kinematic reasons it is often not possible to achieve real translational trajectories by carried flights, particularly in the case of surface-to-surface missiles.
Furthermore, it is known from the prior art to use unmanned missiles as test objects for navigation software. For this purpose, the missile has a fixed navigation system, wherein in a standardized flight a response by the navigation software can be checked. Such a missile is known for example from DE 10 2011 115 963 B3.
An object of the invention is to provide a stationary test device as well as a mobile test device for a missile which with a simple and cost-effective production enable a safe and reliable, and thereby cost-effective, performance of tests of the missile. Finally, an object of the invention is to provide a test system consisting of the aforementioned test devices.
The object is achieved by a mobile test device for a missile comprising a flight platform, a carrier device and a control module. The flight platform is in particular an unmanned, particularly advantageously a non-man-carrying, flight platform. The carrier device is fastened to the flight platform and serves to receive an avionics testpiece of the missile. In this case the carrier device enables a movement of the avionics testpiece in three rotational degrees of freedom. The line of sight for the avionics testpiece and the relative geometry between the center of gravity of the missile and the center of gravity of the target to be approached can preferably be generated by the carrier device. The control module enables the control of the flight platform for taking off on a predetermined reference trajectory. Moreover the control module makes it possible to activate the carrier device for alignment of the avionics testpiece. Finally the navigation data produced by the avionics testpiece can be stored by the control module. Therefore a flight of the missile can be simulated by the mobile test device, wherein in particular the airspeed of the flight platform does not correspond to the airspeed of the missile. Thus, a simulation of the flight is not possible in real time, but only at a slower speed. The navigation data stored by the control module can be used particularly advantageously for the simulation with the stationary test device according to the invention.
The carrier device of the mobile test device is particularly advantageously a gimbal platform. Thus, a simple and efficient alignment of the avionics testpiece is made possible.
The flight platform is preferably a helicopter. Thus, in particular, the capability for vertical takeoff and landings is provided. The flight platform particularly advantageously has at least two horizontal oriented rotors. Since a status control is necessary for such an arrangement of rotors, the control module, as described above, preferably also performs the activation to the flight platform so that a stable flight with the flight platform is enabled by the status control performed by the control module.
Moreover, the invention relates to a test system for a missile, wherein the test system comprises a stationary test device and a mobile test device, also in particular as described above. The stationary test device comprises, in particular, a retaining device and a display device. The retaining device serves, in particular, to receive an avionics testpiece of the missile, wherein the retaining device enables a movement of the avionics testpiece in three rotational degrees of freedom. The display device serves for presentation of information on the surroundings of the missile. The display device can be moved inside a virtual plane, in particular, by a translational carriage system. Thus, the display device is movable in two translational degrees of freedom, so that two translational degrees of freedom of the missile can be simulated. In this way translational degrees of freedom of the missile perpendicular to a longitudinal axis of the missile, or a sight axis of the avionics testpiece, can be simulated. For this purpose, it is provided that the display device can be detected by the avionics testpiece if the avionics testpiece is disposed on the retaining device. If the display device is moved, as described above, a translational movement of the missile is suggested to the seeker head. The display device itself simulates a translational movement of the missile in a third direction of movement, wherein these third direction of movement is in particular oriented parallel to a longitudinal axis of the missile, or to the sight axis of the avionics testpiece. Thus, an OLED screen may be particularly provided as a display device, on which real-time information on surroundings can be displayed by a video system. In this way, a flight of the missile can be simulated realistically, so that also geometric conditions, such as aspect angle, aspect ratio, proximity, image explosion or environmental disturbances (such as change to the lighting conditions), can be simulated realistically. The synchronously required data for the avionics testpiece, such as in particular IMU data, are preferably artificially fed into the avionics testpiece.
The stationary test device preferably has a control unit. A movement of the retaining device and shifting of the display device can be controlled by the control unit. Moreover, it is preferably provided that the aforementioned video system and thus the display on the display device can be controlled by the control unit. In this way, the take-off on a pre-defined reference trajectory can be simulated, wherein the navigation data generated by the avionics testpiece can be stored by the control unit. Particularly preferably the behavior of the missile during the taking off on the reference trajectory has been simulated beforehand by the mobile test device, according to the invention, so that a realistic control of the movement of the retaining device and the shifting of the display device is made possible by the control unit of the stationary test device.
Finally, it is preferably provided that the retaining device is a turntable or a robot.
The test system is preferably characterized in that the stationary test device can be operated with simulation data which can be obtained from measurement data. In this case the measurement data can be captured during the operation of the mobile test device. Thus a, very accurate simulation is made possible by the stationary test device.
Particularly advantageously it is provided that the simulation data which can be obtained from the measurement data received during of the operation of the mobile test device comprise IMU data, GPS data, CAS data and seeker head data.
Finally, the invention relates to a method for testing missiles, in particular with a test system, as described above. A method according to the invention comprises the following steps: First of all a reference trajectory, in particular a three-dimensional and/or translational reference trajectory, is defined. The reference trajectory preferably simulates a relative geometry between the missile and a target to which the missile should fly. In the next step the take-off on the reference trajectory takes place with a mobile test device. In this case it is provided that an avionics testpiece of the missile is disposed on the mobile test device. Navigation data generated by the avionics testpiece during the take-off on the reference trajectory are particularly advantageously recorded. In a last step a simulation of a movement of the missile takes place with a stationary test device. In this case, the avionics testpiece is disposed on the stationary test device. The simulation takes place with reference to simulation data which are based on the measurement data obtained during the take-off on the reference trajectory with the mobile test device. Thus, a very accurate simulation of the missile is possible, so that a plurality of flight tests can be simulated in advance by the stationary test device.
Further details, advantages and features of the present invention are apparent from the following description of exemplary embodiments with reference to the drawings. In the drawings: